Molding apparatus



April 25, 1933. G, ZIMMERMANN MOLDING APPARATUS Filed Jan. 23, 1931 alle@ Patented Apr. Z5, 1933 UNITED STATES GUsTAv ZIMMERMANN, or nUssELDonr, GERMANY HOLDING Arrannirus Application led January 23, 1931, Serial. No.

My invention relates to apparatus for producing molds and cores? for foundries, and particularly to apparatus employing' compressed air to force dry sand from a container into molding or core boxes.

Oneobject of the invention is to provide a device which can be used in many Ways andrwhichattains its object by very simple means. Y 1

Another object of the invention is to prevent sand from sticking to its container by providing means whiclii counteract this tendency and which require no special attendance.

With the foregoing and minor objects in view, the invention resides in the novel subject matter hereinafter described and claimed, the description being supplemented by the accompanying drawing, in which Figure 1 is a vertical section of the device according to the invention.v Figure 2 is a detail sectional view of the rod, sleeve and end connections, in which the sleeve is shown so arranged that its flange or collar 22 closes the inlet opening 23 in the upper end of the container. Figure 3 is a similar View of the same in which the constructionof the 'tube is modified so that its inlet openings 21 can be closed and the opening 23 kept open so that compressed air can enter the container only through said opening 23. Figure 4 is a detail elevation of the worm bush which is fast to therod 3. Figure 5 is a detail sectional view of the sleeve nut which cooperates with the worm bush to Vcause the axially movable rod 3" to impart rotary movement to the tube. Figure 6 is a detail elevation of the rod, tube, guiding sleeve and sleeve nut assembly for causing the axially movable rod to impart rotary movement-to the tube.

, In the drawing above briefly described, the numeral 1 designates a sand container to be filled with molding sand by means of an attachment not shown, the container being` 510,803; and'in Germany January 28,- 1930.

provided with a lower nozzle 2 adapted to be shut off by the rod 3 which can move up v and down and is guided in the cover ,4 of the lpotlike top structure 5 ofthe containerv The rod 3 is connectedon top with ato double-armed lever rotatably disposed in the bracket 7 of theY covera4 and connected with a bar 8 `adapted to be moved rup 'andl down by the adjustment of a lever 9, the,4 adjustment being efected by a hand lever,"" not shown. Normally, a spring 10 keeps the bar 8 in its highest position so that ythe opening of the nozzle is closed completely by thehead of the rod 3. i Y Firmly connected with the rod 3 is a bush" 00 11 having a very coarse male thread and being arranged in a nut 12 provided with a corresponding thread, the 'bush 11 Vbeing held axially rotatable by the cover '4 and the sleeve 13 which is axially rotatably sup- 65 ported by the potlike structure 5. The nut 12 has a lateral projection' 14 iny which a pawl V15 is held byy the pin' 16 so as to be loosely rotatable. The pawl`15 engages with its free end the teeth 17 ofthe'edge 18 of 70 the sleeve13 wherein the tube 19 is adjustably held by the screw 20. The tube 19v is provided with the openings 21v and a circular collar 22 which fits into, and packs, the opening 23 in the top of the container 1 75 At its lower part the tube 19 is fitted with the radialvanes 24;.

When molding is to take place, compressed air is supplied to the device through the piping 25.V By lowering the bar 8 and raising thereby the rod l3 the opening vof the nozzle 2 is released to discharge sand into flasks or core boxes keptV underneath. The action of the 'air is two-fold,v the air passingbetween` the bore 23 and the tube 19 having a pressing 85 effect upon the sand from above while a suction effect is created by the airwhich has entered, through the apertures 21, the tube 19 and is discharged from its lower end at great speed. `During the upward motion of the rod 3 the` bush 11 attached toit turns the nut 12 in such a way that the pawl 15 will rotate the sleeve 13 and thus the tube 19. The vanes 24 cooperate in this motion and prevent thereby that the sand sticks to the container 1.

When the tube 19 is secured in the sleeve 13 so that the collar 22 closes the opening 23, as shown in Fig. 2, compressed air can enter the tube 19 only through the openings 21 and flow out at the lower end thereof with the result that it. exerts in the` main a suction effect upon'the sandv to be conveyed'.

If the tube 19, as shown in Fig. 3, is clamped in the sleeve 13 so high that the openings 21 are covered and` the Vcollar 22 blocks up the aperture 23, compressed air can enter the container 1 through theY opening 23. only. and the sand can be .thrown out only by the pressure exerted by the air on .f the toplayer. 'PhedeviceA according to they invention makes it possible therefore to work either with air pressure or suction air or both, and is thusnadapted to handle allsorts of dry and molding. sand under any conditions.

The device may be placed directly on the flask or" molding box toghel filled or be arrangedat a distancev therefrom.

Should the motion oit' the agitator at ,the

opening of `the nozzle not vsuffice for veryv sticky dry sand, the latter` can ybe' stirred constantly by slightlyv and uninterruptedly.

lowering and raising the rod-- 3 during the kentire 'moldingv process.. Furthermore, in

'special cases the tube 19. might.` be turned .only during. thedescent of? the rod 3 by 'disposing the -pawl '15 so that it acts towards thel other side.

n Instead of the'vanes 24 ordinary rods arranged radially or paralleltol the tube 19, or similar means, may be employed.

IV am aware that prior tol my invention apparatus adaptedl to molddirectly by compressed, air has. been proposed already, and IV do not, therefore, claim such apparatus What I claim.y z. l.. The combination in: a sandv molding machine of a closed.. receptacle for molding sand, having.l a.. discharge opening in the container for sand, having, a discharge nozzle at the lower endV and an. airinlet opening, at the upper end, an axially movable l rod extending through the. container toopen and'V close the. nozzle, av tube surrounding the rod, and the boreo which isv ory greater diameter thanthe` rod and said: tube having` an air inlet opening near its upper end, and means to supply compressed air to the inlet openings of the container and the tube.

3. Molding apparatus, comprising a closed container for sand, having a discharge nozzleat the lower end and an air inlet opening at the upper end, an axially movable rod extending through the container to open and close the nozzle, a vertically movable tube surrounding the rod, and the bore of which is of greater diameter than the rod and said tube having an air inlet opening near its upper, engdilshiftable into and outof connection with the air opening of the container, and means to supply compressed air 'to the inletuopenings'of the container and hasa; circular collar,the aperturethe said cover itting the said collar'.V

5. The combination accordingto claim 1,

-in which Va tube:` adapted: to be: raisedfand lowered surroundsy the rod, a sleeve is con-:

nected with the rod, and a guide. keeps the said sleeve rotatable..

6. Thecombination according to? claim 1, in which a tube adapted to be raised and klowered surrounds the rod, a sleeve is con-fnectediwith the rod, teeth are. disposed on theV saicl' sleeve, a pawl isprovided.' for the said teeth a nut carries the pawl, and a threaded bush in the nut is firmly connected with the rod.

.7. Molding Vapparatus comprising nozzle at the lower end and an air inlet opening. at the. upper end', an axially movable and `elosethe nozzle', ak revoluble. tube through which the rode-Xtends and-the. bore ofy which is of greater diameter than thev rod, said tube having agitator elements and alsovha-ving an airinletopenin-g near its upper end,; means to supply compressed air to the inlet openings of the container andtube, means to impart upward and downward axiali movements` to the rodv and means operated by the rod to impart rotary movementto the tube. 8. Apparatus as claimed in claim 7, including alever to aotuate the rod, a vertically movable rod connected to said lever and a spring active on` the last named rod to cause said rod. and lever to normally holdv the first named. rod in nozzle closing position.

9. Apparatus as claimed in claim 7, including `a guiding and holdingsleeve in which the upper portion of the tube is sesnv cured and in which the tube has arflange collar spaced :from its air inlet opening; and adapted to close the air inlet opening of the container when the tubew in one adjusted position; f

a 'closed container for sand having a. discharge rod extending through the container to openf 10. Apparatus as claimed in claim 7, in which the means to cause the rod to impart rotary movement to the tube comprises e Worm bush fast to the rod, a sleeve nut engaged by said Worm bush, a guiding and holding sleeve in which the upper end of the tube is secured, said guiding and holding sleeve being provided with ratchet teeth and a. pawl pivotally mounted on the sleeve nut and engageable with said ratchet teeth.

In testimony whereof I have afpixed my signature.

GUSTAV ZIMMERMANN. 

